To Switch Snap to Grid
1. Select Tools > Environment. The Environment dialog box opens.
2. In the Default actions box, check or clear Snap to grid and Snap to XY axes as required.
If grid snap is on, objects only snap to the grid if the grid spacing is set large enough to be visible. On an A-size drawing, the grid is not visible if the grid spacing is less than 0.7 mm or 0.07 inches.
The visibility of the drawing also depends on the size of the window and whether you have collapsed the left panel of the window or not.
3. Click Apply or OK for the changes to affect your current diagram.